Description: Any subset of the base set has an LUB in a complete lattice. (Contributed by NM, 14-Sep-2011)
Ref | Expression | ||
---|---|---|---|
Hypotheses | clatlubcl.b | |- B = ( Base ` K ) |
|
clatlubcl.u | |- U = ( lub ` K ) |
||
Assertion | clatlubcl | |- ( ( K e. CLat /\ S C_ B ) -> ( U ` S ) e. B ) |
Step | Hyp | Ref | Expression |
---|---|---|---|
1 | clatlubcl.b | |- B = ( Base ` K ) |
|
2 | clatlubcl.u | |- U = ( lub ` K ) |
|
3 | eqid | |- ( glb ` K ) = ( glb ` K ) |
|
4 | 1 2 3 | clatlem | |- ( ( K e. CLat /\ S C_ B ) -> ( ( U ` S ) e. B /\ ( ( glb ` K ) ` S ) e. B ) ) |
5 | 4 | simpld | |- ( ( K e. CLat /\ S C_ B ) -> ( U ` S ) e. B ) |